// JavaScript Document
jQuery
		.extend({

			createUploadIframe : function(id, uri) {
				// create frame
				var frameId = 'jUploadFrame' + id;

				if (window.ActiveXObject) {
					if(document.documentMode <9){  
				        var io = document.createElement('<iframe id="' + frameId + '" name="' + frameId + '" />');  
				        if(typeof uri== 'boolean'){  
				            io.src = 'javascript:false';  
				        }  
				        else if(typeof uri== 'string'){  
				            io.src = uri;  
				        }  
					}else{  
						  var io = document.createElement('iframe');  
					        io.id = frameId;  
					        io.name = frameId;
				    }  
					//IE END	
				} else {
					var io = document.createElement('iframe');
					io.id = frameId;
					io.name = frameId;
				}
				io.style.position = 'absolute';
				io.style.top = '-1000px';
				io.style.left = '-1000px';

				document.body.appendChild(io);

				return io;
			},
			createUploadForm : function(id, fileElementId, data) {
				// create form
				var formId = 'jUploadForm' + id;
				var fileId = 'jUploadFile' + id;
				var form = jQuery('<form  action="" method="POST" name="'
						+ formId + '" id="' + formId
						+ '" enctype="multipart/form-data"></form>');
				var oldElement = jQuery('#' + fileElementId);
				var newElement = jQuery(oldElement).clone();
				jQuery(oldElement).attr('id', fileId);
				jQuery(oldElement).before(newElement);
				jQuery(oldElement).appendTo(form);
				//增加文本参数的支持  

		        if (data) {  

		            for (var i in data) {  

		                $('<input type="hidden" name="' + i + '" value="' + data[i] + '" />').appendTo(form);  

		            }  

		        }  
				// set attributes
				jQuery(form).css('position', 'absolute');
				jQuery(form).css('top', '-1200px');
				jQuery(form).css('left', '-1200px');
				jQuery(form).appendTo('body');
				return form;
			},

			ajaxFileUpload : function(s) {
				// TODO introduce global settings, allowing the client to modify
				// them for all requests, not only timeout
				s = jQuery.extend({}, jQuery.ajaxSettings, s);
				var id = s.fileElementId;
//				var form = jQuery.createUploadForm(id, s.fileElementId);
				var form = jQuery.createUploadForm(id, s.fileElementId, s.data);  
				var io = jQuery.createUploadIframe(id, s.secureuri);
				var frameId = 'jUploadFrame' + id;
				var formId = 'jUploadForm' + id;

				if (s.global && !jQuery.active++) {
					// Watch for a new set of requests
					jQuery.event.trigger("ajaxStart");
				}
				var requestDone = false;
				// Create the request object
				var xml = {};
				if (s.global) {
					jQuery.event.trigger("ajaxSend", [ xml, s ]);
				}

				var uploadCallback = function(isTimeout) {
					// Wait for a response to come back
					var io = document.getElementById(frameId);
					try {
						if (io.contentWindow) {
							xml.responseText = io.contentWindow.document.body ? io.contentWindow.document.body.innerHTML
									: null;
							xml.responseXML = io.contentWindow.document.XMLDocument ? io.contentWindow.document.XMLDocument
									: io.contentWindow.document;

						} else if (io.contentDocument) {
							xml.responseText = io.contentDocument.document.body ? io.contentDocument.document.body.innerHTML
									: null;
							xml.responseXML = io.contentDocument.document.XMLDocument ? io.contentDocument.document.XMLDocument
									: io.contentDocument.document;
						}
					} catch (e) {
						jQuery.handleError(s, xml, null, e);
					}
					if (xml || isTimeout == "timeout") {
						requestDone = true;
						var status;
						
							status = isTimeout != "timeout" ? "success"
									: "error";
							// Make sure that the request was successful or
							// notmodified
							if (status != "error") {
								// process the data (runs the xml through
								// httpData regardless of callback)
								var data = jQuery.uploadHttpData(xml,
										s.dataType);
								if (s.success) {
									// ifa local callback was specified, fire it
									// and pass it the data
									s.success(data, status);
								}
								;
								if (s.global) {
									// Fire the global callback
									jQuery.event.trigger("ajaxSuccess", [ xml,
											s ]);
								}
								;
							} 
							else 
							{
								jQuery.handleError(s, xml, status);
							}

						
						if (s.global) {
							// The request was completed
							jQuery.event.trigger("ajaxComplete", [ xml, s ]);
						}
						;

						// Handle the global AJAX counter
						if (s.global && !--jQuery.active) {
							jQuery.event.trigger("ajaxStop");
						}
						;
						if (s.complete) {
							s.complete(xml, status);
						}
						;

						jQuery(io).unbind();

						setTimeout(function() {
							try {
								jQuery(io).remove();
								jQuery(form).remove();

							} catch (e) {
								jQuery.handleError(s, xml, null, e);
							}

						}, 100);

						xml = null;

					}
					;
				}
				// Timeout checker
				if (s.timeout > 0) {
					setTimeout(function() {

						if (!requestDone) {
							// Check to see ifthe request is still happening
							uploadCallback("timeout");
						}

					}, s.timeout);
				}
				try {
					var form = jQuery('#' + formId);
					jQuery(form).attr('action', s.url);
					jQuery(form).attr('method', 'POST');
					jQuery(form).attr('target', frameId);
					if (form.encoding) {
						form.encoding = 'multipart/form-data';
					} else {
						form.enctype = 'multipart/form-data';
					}
					jQuery(form).submit();

				} catch (e) {
					jQuery.handleError(s, xml, null, e);
				}
				if (window.attachEvent) {
					document.getElementById(frameId).attachEvent('onload',
							uploadCallback);
				} else {
					document.getElementById(frameId).addEventListener('load',
							uploadCallback, false);
				}
				return {
					abort : function() {
					}
				};

			},

			uploadHttpData : function(r, type) {
				var data = !type;
				data = type == "xml" || data ? r.responseXML : r.responseText;
				// ifthe type is "script", eval it in global context
				if (type == "script") {
					jQuery.globalEval(data);
				}
				if (!((navigator.userAgent.indexOf('MSIE') >= 0) &&(navigator.userAgent.indexOf('Opera') < 0))) {
					try {
						data = jQuery.parseJSON(jQuery(data).text());
					} catch (e) {
						data = "";
					}
				} 
				else
				{
					try {
						if (type == "json") {eval("data = " + data);}
					} catch (e) {
						data = "";
					}
				}
				
				// evaluate scripts within html
				if (type == "html") {
					jQuery("<div>").html(data).evalScripts();
				}

				return data;
			}
		});
